Justin Bieber is celebrating his 19th birthday with a circus-themed party.The 'Baby' singer turns 19 today (01.03.13) and he wants to mark the occasion in style so has arranged a big bash in London this evening which features clowns and a ringmaster.Justin - who is currently in the UK touring - and 20 friends have a £10,000 budget for the night and had been scoping out the perfect venue over the past few weeks.A source told the Daily Mirror newspaper: "Justin wants to celebrate in style and he loves clubbing in London. It's no accident that there's a break in his UK tour which coincides with his birthday."He's been looking for the perfect venue and finally settled on Cirque Du Soir as he loves the kitsch theme. The venue is all ready for him, with clowns, goblins, aerial acts and some fire-eaters."Justin's rumoured new girlfriend, Ella-Paige Roberts Clarke is expected to be at the bash as the pair have been inseparable in recent weeks.Â Last year, Justin celebrated his 18th birthday by being given a £65,000 Fisker Karma car by his manager Scooter Braun.